Regularization of brane induced gravity

Abstract

We study the regularization of theories of ''brane induced'' gravity in codimension NϾ1. The brane can be interpreted as a thin dielectric with a large dielectric constant, embedded in a higher dimensional space. The kinetic term for the higher dimensional graviton is enhanced over the brane. A four dimensional gravitation is found on the brane at distances smaller than a critical distance rϽr c , and is due to the exchange of a massive resonant graviton. The crossover scale r c is determined by the mass of the resonance. The suppression of the couplings of light Kaluza-Klein modes to brane matter results in a higher dimensional force law at large distances. We show that the resulting theory is free of ghosts or tachyons.

Induced gravity in orientifold models

“…With a codimension greater than one the effects of a finite brane thickness can no longer be neglected ([8] - [12]), but the conclusions on the crossover scale or on the need for compactification remain the same. On the other hand one can also merge the setups of Randall-Sundrum and of DvaliGabadadze-Porrati [13].…”

Effective description of brane terms in extra dimensions

“…Moreover, it agrees with completions such as deconstructed orbifolds. The less common works including orthogonal terms use fat branes [46] or treat the orthogonal brane terms perturbatively to first order [9], which is non-singular. The first possibility reduces to the renormalized effective theory at scales lower than the physical width of the branes.…”

UV caps, IR modification of gravity, and recovery of 4D gravity in regularized braneworlds

“…In addition to this natural geometrical asymmetry, we allow the cap Planck scale, M C , to differ from that in the bulk, M B . If M C ≫ M B , this leads to an explicit realization of the regularization of brane-induced gravity [17]. The purpose of the present paper is to investigate in detail the behavior of weak gravity in such a braneworld.…”

“…(The divergence is the generic feature for N ≥ 2.) If one is to resolve this short distance singularity somehow, the regularization at UV will affect the behavior of gravity at IR [13,14,15,16,17,18]. (See also different approaches to construct higher codimension braneworlds with induced gravity [19,20].…”